Power grid braces for more electric cars

San Diego is leading the rest of the country in putting electric cars on the road and is building an infrastructure of charging stations to support an expected influx of plug-in vehicles over the next few years. U-T

San Diego is leading the rest of the country in putting electric cars on the road and is building an infrastructure of charging stations to support an expected influx of plug-in vehicles over the next few years. U-T

A consortium of major automakers and U.S. utilities has set out to create an digital Rosetta Stone to help electric cars communicate with the power grid.

The effort aspires to create a widely accepted communication standard that can send signals to electric vehicles, regardless of make or model, to slow or pause the charging of batteries.

Architects of that link say it can help make the grid more clean and efficient as electric vehicles catch on with drivers, shifting the nation’s transportation energy needs from crude oil to electricity.

There are currently some 230,000 consumer plug-in vehicles on U.S. roads, with 40 percent of them in California. Each can draw energy from the grid equivalent to a home air-conditioning system. But unlike air conditioning, power demands from electric vehicles can be staggered and shifted throughout the day and night to avoid overwhelming the grid.

That ultimately may reduce commodity costs and infrastructure needs, with savings passed along to consumers who opt to participate, David McCreadie, manager of electric vehicle infrastructure and smart grid at Ford Motors, said earlier this week.

“The reason why you as a driver of a car should care about any of this is, frankly, there is money on the table and utilities are willing to pay for your help,” he said.

Pilot trials are being conducted on cars owned by automakers, but real-world tests involving privately owned vehicles are coming as soon as next year. Engineers already are dreaming of green charging options that might match notify cars during a surge of solar or wind energy.

The project is an outgrowth of a decade of research efforts at the nonprofit Electric Power Research Institute. Sumitomo Electric of Japan will develop the core software platform. Communication between cars and utilities would flow through remote computer servers, much like other cloud computing.

San Diego Gas & Electric is among the initial 15 utilities participating in the project. Eight automakers have signed on: Honda, BMW, Chrysler, Ford, General Motors, Mercedes-Benz, Mitsubishi and Toyota. Plug-in electric vehicle pioneers Nissan and California-based Tesla Motors are notably absent, but could sign on later.

Success will hinge on convenience for customers and providing a fully charged vehicle at the appointed time, according to Dan Bowermaster, program manager for electric transportation at the Electric Power Research Institute.

Most plug-in electric cars already provide time-delayed charging that can be set to a deadline, be it 5 a.m. or 5 p.m.

By aligning car charging with periods of cheap, plentiful electricity generation, utilities eventually should be able to pull back on some investments for transmission lines, power plants and substations. How much will they save?

“That is literally the million-dollar question,” Bowermaster said. “What are the benefits for your local utility to defer and eliminate infrastructure projects?”

Vehicle batteries eventually might be called on to feed electricity back into the grid to help balance supply and demand for electricity.

SDG&E already provides two special billing rates for electric vehicle users. Prices are determined by the time of day, currently providing low-cost vehicle charging between midnight and 5 a.m.

“It will be important to have technology that gives our customers the opportunity to charge their cars at times of day when the supply of energy is low-cost and the capacity of our grid is plentiful,” SDG&E spokeswoman Erin Coller said.

California wants to put 1.5 million zero-emission vehicles on the road by 2025, offering cash rebates among a broad palate of incentives.